Oyster knife



FIG. 1 is a perspective view of the ornamental design for an oyster knife according to the present invention.

FIG. 2 is a right-side view of the oyster knife shown in FIG. 1.

FIG. 3 is a left-side view of the oyster knife shown in FIG. 1, opposite the right-side view of FIG. 2.

FIG. 4 is a top view of the oyster knife shown in FIG. 1.

FIG. 5 is a bottom view of the oyster knife shown in FIG. 1, opposite the top view shown in FIG. 4.

FIG. 6 is a front view of the oyster knife shown in FIG. 1; and,

FIG. 7 is a back view of the oyster knife shown in FIG. 1, opposite the front view shown in FIG. 6. 

CLAIM The ornamental design for an oyster knife, as shown and described. 